JVC-MXJ680V-cs-sm维修电路原理图.pdf

SERVICE MANUAL COPYRIGHT 2000 VICTOR COMPANY OF JAPAN, LTD. MX-J570V MX-J680V No.20853 Jul. 2000 COMPACT COMPONENT SYSTEM MX-J570V MX-J680V Safety precautions Important for laser products Preventing static electricity Precautions at disassembling and parts replacement Disassembly method Adjustment method 1-2 1-3 1-4 1-5 1-6 1-29 Diagnosis which uses extension wire method Flow of functional operation until TOC read Maintenance of laser pickup Replacement of laser pickup Description of major ICs 1-33 1-34 1-35 1-35 1-36 Contents Area Suffix US UX Singapore Saudi Arabia SUPER VIDEO TAPE A/B FADE MUTING ON SCREEN NEXTPREV RMSMXJ570V REMOTE CONTROL SLEEPECHO SOUND MODE VOCAL MASKING REC START/STOP ACTIVE BASS EX. SUBTITLEHIGHLIGHT FM MODE STILLV.INTRO KEY CONTROL Each difference point Model CD/DECK/RECEIVERSPEAKER MX-J680V CA-MXJ680V MX-J570V CA-MXJ570VSP-MXJ570V SP-MXJ680V Color Tray fitting Silver Light blue Gray Silver TW2111A, Reverse ; TW2121A Fast Forward and Rewind ; TW2231A 9. Test disc : CTS-1000(12cm),GRG-1211(8cm) 10. Jitter meter Measurement conditions Power supply voltage AC110/127/220/230-240V(50Hz) Measurement output terminal : Speaker out :TP101(Mesuring for TUNER/DECK/CD) :Dummy load 6ohm Radio input signal AM modulation frequency : 400Hz Modulation factor : 30% FM modulation frequency : 400Hz Frequency displacement : 22.5kHz Frequency Range AM531kHz1710kHz FM87.5MHz108MHz Standard measurement positions of volume and switch Power : Standby (Light STANDBY Indicator) S,A,BASS : OFF Sound mode : OFF Main VOL. : 0 Minimum Travers mecha set position : Disc 1 Mic MIX VOL : MAX ECHO : OFF Precautions for measurement 1. Apply 30pF and 33kohm to the IF sweeper output side and 0.082 F and 100kohm in series to the sweeper input side. 2. The IF sweeper output level should be made as low as possible within the adjustable range. 3. Since the IF sweeper is a fixed device, there is no need to adjust this sweeper. 4. Since a ceramic oscillator is used, there is no need to perform any MPX adjustment. 5. Since a fixed coil is used, there is no need to adjust the FM tracking. 6. The input and output earth systems are separated. In case of simultaneously measuring the voltage in both of the input and output systems with an electronic voltmeter for two channels, therefore, the earth should be connected particularly. 7. In the case of BTL connection amplifier, the minus terminal of speaker is not for earthing. Therefore, be sure not to connect any other earth terminal to this terminal. This system is of an OTL system. MX-J570V/MX-J680V 1-30 Arrangement of adjusting positions Cassette mechanism section (Mechanism A section)Cassette mechanism section (Back side) Cassette mechanism unit section Head azimuth adjusting screw (Forward side) Head azimuth adjusting screw (Reverse side) Head azimuth adjusting screw (Forward side) Head azimuth adjusting screw (Reverse side) Playback head Playback,recording and eraser heads or playback head Tape speed ADJ Bias ADJ L Bias ADJ R MX-J570V/MX-J680V 1-31 1.Playback the test tape TMT7036(10kHz). 2.With the playback mechanism or recording playback mechanism, adjust the head azimuth screw so that the forward and reverse output levels become maximum.After adjustment,lock the head azimuth at least by half a turn. 3.In either case,this adjustment should be performed in both the forward and reverse directions with the head azimuth screw. Adjust VR301 so that the frequency counter reading becomes 3,000Hz60Hz when playing back the test tape VTT712(3kHz)with the playback mechanism or playback and recording mechanism after ending forward winding of the tape. Confirmation of head angle Confirmation of tape speed Test tape :TMT7036(10kHz) Measurement output terminal :Speaker terminal Speaker R (Load resistor:3) :Headphone terminal Test tape :VTT712(3kHz) or TMT7036(3kHz) Measurement output terminal :Headphone terminal Maximum output Tape speed of decks (A and B) :3,000Hz 60Hz Adjust the head azimuth screw only when the head has been changed. VR301 ItemsMeasurement conditions Measurement method Standard values Adjusting positions Tape recorder section ItemsMeasurement conditions Measurement method Standard values Adjusting positions After setting to the double speed motor, confirm that the frequency counter reading becomes 4,800+400/-300Hz when the test tape VTT712 (3kHz) has been play back with the playback mechanism. When the test tape VTT712(3kHz) has been played back with the playback mechanism or recording and playback mechanism at the beginning of forward winding, the frequency counter reading of the difference between both of the mechanisms should be 6.0Hz or less. When the test tape VTT712(3kHz) has been played back with the playback mechanism or recording and playback mechanism at the beginning of forward winding the frequency counter reading of wow flutter should be 0.25 or less(WRMS). Double tape speed Difference between the forward and reverse speed. P.mecha and R/P mecha speed Wow flutter Test tape :TMT7036(10kHz) Measurement output terminal :Speaker terminal Speaker R (Load resistance:3) measurement output terminal :Headphone terminal Test tape :TMT7036(10kHz) Measurement output terminal :Headphone terminal 4,800+400/ -300Hz 60Hz or less with in 0.25% JIS(WTD) Playback mechanism side Both the playback and recording playback mechanism Both the playback and recording playback mechanism Reference values for confirmation items MX-J570V/MX-J680V 1-32 ItemsMeasurement conditions Measurement method Standard values Adjusting positions 1.With the recording and playback mechanism, load the test tapes(AC-514 to TYP and AC-225 to TYP),and set the mechanism to the recording and pausing conditions in advance. 2.After connecting 100in series to the recorder head,measure the bias current with a valve voltmeter at both of the terminals. 3.After resetting the PAUSE mode,start recording. At this time,adjust VR101 for LcH and VR201 for RcH so that the recording bias current values become 4.0A (TYP) and 4.20A(TYP). 1.With the recording and playback mechanism,load the test tape(AC-514 to TYP),and set the mechanism to the recording and pausing condition in advance. 2.While repetitively inputting the reference frequency signal of 1kHz and 10kHz from OSC IN, record and playback the test tape. 3.While recording and playing back the test tape in TYP,adjust VR101 for LcH and VR201 for RcH so that the output deviation between 1kHz and 10kHz becomes -1dB2dB. Adjustment of recording bias current (Reference value) Adjustment of recording and playback frequency characteristics *Mode : Forward or reverse mode *Recording mode *Test tape :AC-514 and AC-225 Measurement output terminal :Both recording and headphone terminals Reference frequency :1kHz and 10kHz (REF:-20dB) Test tape :TYPAC-514 Measurement input terminal :OSC IN AC-225 :4.20A AC-514 :4.0A Output deviation between 1kHz and 10kH :-1dB2dB LcH :VR101 RcH :VR201 LcH :VR101 RcH :VR201 Electrical performance ItemsMeasurement conditions Measurement method Standard values Adjusting positions 1.While changing over to and from BIAS 1 and 2, confirm that the frequency is changed. 2.With the recording and playback mechanism. load the test tape (AC-514 to TYP),and set the mechanism to the recording and pausing conditions in advance. 3.Confirm that the BIAS TP frequency on the P.C.board is 100kHz6kHz. 1.With the recording and playback mechanism, load the test tapes(AC-514 to TYP and AC-225 to TYP),and set the mechanism to the recording and pausing condition in advance. 2.After setting to the recording conditions,connect 1M in series to the eraser head on the recording and playback mechanism side,and measure the eraser current from both of the eraser terminal. Recording bias frequency Eraser current (Reference value) *Recording and playback side forward or reverse *Test tape :TYPAC-514 *Measurement terminal BIAS TP on P.C.board *Recording and playback side forward or reverse *Recording mode *Test tape :AC-514 and AC-225 Measurement terminal Both of the eraser head 100kHz +9kHz -7kHz TYP :120mA TYP :75mA Reference values for electrical function confirmation items MX-J570V/MX-J680V 1-33 FLAT WIRE FLAT WIRE QUQ412-4020CJ JIG-MXJ500CONNECTOR Board x 2 CONNECTOR Board x 2 Diagnosis which uses extension wire method System control P.C.board 1.Remove the metal cover and CD changer mechanism. 2.Remove the front panel assembly. 3.One screw A is removed, and relay board is removed. 4.As shown in fig.1, place the front panel assembly after opening it outward using the right side of the front panel as an axis. 5.The extension wire is connected with CN870 & CN871 on the INPUT/OUTPUT board and CN860 & CN861 on the main board. Extension wire parts No. Extension wire Input/output board Main board Relay board Relay board CN870 A CN860 CN871 CN861 Fig.1 Front panel assembly MX-J570V/MX-J680V 1-34 Flow of functional operation until TOC read Slider turns REST SW ON. Automatic tuning of TE offset Laser ON Detection of disc Automatic measurement of Focus S-curve amplitude Automatic tuning of Focus offset Disc is rotated Focus servo ON (Tracking servo ON) Automatic tuning of Tracking error balance Automatic measurement of Tracking error amplitude Automatic tuning of Focus error balance Disc to be braked to stop Tracking servo on states Tracking servo off states Disc states to rotate TOC reading finishes Automatic measurement of TE amplitude and automatic tuning of TE balance 500mv/div 2ms/divFig.1 Approx.3sec pin 25 of IC601(TE) Approx 1.8V VREF Tracking error waveform at TOC reading Power ON Play Key Confirm that the Focus error S-cuve signal at the pin28 of IC651 is approx.2Vp-p Confirm that the signal from pin24 IC651 is 0V as a accelerated pulse during approx.400ms. Confirm the waveform of the Tracking error signal. at the pin 25 of IC601 (R604) (See fig-1) Automatic tuning of Focus error gain Automatic tuning of Tracking error gain TOC reading Play a disc Confirm the eys-pattern at the lead of TP1 Confirm that the voltage at the pin5 of CN801 is HLH. Check Point Check that the voltage at the pin40 of IC651 is + 5V? MX-J570V/MX-J680V 1-35 Turn off the power switch and,disconnect the power cord from the ac outlet. Replace the pickup with a normal one.(Refer to Pickup Removal on the previous page) Plug the power cord in,and turn the power on. At this time,check that the laser emits for about 3seconds and the objective lens moves up and down. Note: Do not observe the laser beam directly. Play a disc. Check the eye-pattern at TP1. Finish. Maintenance of laser pickup (1) Cleaning the pick up lens Before you replace the pick up, please try to clean the lens with a alcohol soaked cotton swab. (2) Life of the laser diode When the life of the laser diode has expired, the following symptoms will appear. 1. The level of RF output (EFM output:ampli tude of eye pattern) will below. Is the level of RFOUT under 1.25V0.22Vp-p? Replace it. NO YES O.K (3) Semi-fixed resistor on the APC PC board The semi-fixed resistor on the APC printed circuit board which is attached to the pickup is used to adjust the laser power.Since this adjustment should be performed to match the characteristics of the whole optical block, do not touch the semi-fixed resistor. If the laser power is lower than the specified value,the laser diode is almost worn out, and the laser pickup should be replaced. If the semi-fixed resistor is adjusted while the pickup is functioning normally,the laser pickup may be damaged due to excessive current. Replacement of laser pickup MX-J570V/MX-J680V 1-36 AN8806SB-W (IC601) : RF&Servo AMP PD LD LDON LDP VCC RF- RF OUT RF IN C.AGC ARF C.ENV C.EA CS BDO BDO CS BRT OFTR /NRFDET GND PDAC PDBD PDF PDE PDER PDFR TBAL FBAL EF- EF OUT TE- TE OUT CROSS TE BPF VDET LD OFF VREF ENV 302425262322143 33 32 34 31 36 35 13 14 15 16 20 2 21 629728 27891017111219 ENV CURCUITRF DET AGC EQ BDO OFTR - + - + - + - +- + - + - + - + - + - + - + - + - + - + -+ - + - + - + VCBA VCBA VCBA VCBA - + 1.Pin layout 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19 2.Block diagram Description of major ICs MX-J570V/MX-J680V 1-37 35 36 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 3. Pin function PD AC FBAL TBAL PDFR PDER PDF PDE PD BD TE BPF VDET CROSS TE OUT TE- FE OUT FE- /NRFDET GND LD OFF VREF ENV OFTR C.AGC ARF C.ENV C.EA CS BDO BDO CS BRT LD LD ON LDP VCC RF- RF OUT RF IN PD Pin No.SymbolI/O I O I - - I O I I/O O I/O I/O I/O O I/O O O - O O - O I O O I O I I I I/O I/O I I I II-V amp input I-V amp input I-V amp input I-V amp input E I-V amp gain control F I-V amp gain control Tracking balance control Focus balance control Inverse input pin for focus error amp Output pin of focus error Inverse input pin for tracking error amp Tracking error signal output Tracking error cross output Input pin of tracking error through BPF Vibration detection signal output Connect to ground Reference voltage output Description APC amp input terminal APC amp output terminal APC ON/OFF control terminal Envelope output Ground RF detection signal output Of-track status signal output BDO output pin A capacitor is connected to this terminal to detect the envelope of RF signal RF output Connecting pin of AGC loop filter RF input RFamp output Inverse input pin for RF amp Power supply Connect to ground A capacitor is connected to this terminal to detect the envelope of RF signal A capacitor is connected to detect the lower envelope of RF signal A capacitor is connected to detect the lower envelope of RF signal MX-J570V/MX-J680V 1-38 1OUT1 2-IN1 3+IN1 4 8 7 6 5VEE VCC OUT2 -IN2 +IN2 2 1 - +- + BA15218 (IC526) : OP AMP. GP1U281X (IC915) : Receiver for remote controller + GND B.P.F VCCVout Amp. LimiterIntegratorComparator Demodulator 7654321 REC SW GND P / B SW CONT. GND VCC P / B SW BA3126N (IC301) : SWITCH 1. Terminal layout and Block diagram 89 GND REC SW MX-J570V/MX-J680V 1-39 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 BIASC VREFC RPEF NC NC NC CIN AIN VCC SPI-A SPI-B SPI-C SPICSB NC NC TEST AOUT GND Decoupling condenser connection terminal. Decoupling condenser connection terminal. Reference resistance connection terminal. Non connect. Non connect. Non connect. Connected to GND of audio system through a condenser. Inputs the audio signal through a condenser. Power supply terminal. Output selection control terminal. Output selection control terminal. Output selection control terminal. Output selection control terminal. Non connect. Non connect. Connected to GND upon normal use. Multi-plexor output terminal. Connect to GND. - - - - - - -